1. Field of the Invention
The present invention relates to a thin film magnetic head having a cobalt-iron-boron core.
2. Description of the Prior Art
Thin film magnetic read/write heads are used for magnetically reading and writing information on a magnetic storage medium such as a magnetic disk or magnetic tape. As data storage requirements have risen, it has become increasingly desirable to provide high levels of information storage densities on the magnetic storage medium. Increased storage densities require magnetic read/write heads which provide a strong writing field in relation to the applied writing current and high permeability for large signal output. This may be achieved by making the anisotropy field (H.sub.k) as small as possible thereby increasing the permeability (.mu.). Increased .mu. also results in increased sensitivity when information is read from the magnetic storage medium. Smaller coercivity (H.sub.c) in a read/write magnetic head is also desirable.
U.S. Pat. No. 4,661,216 relates to a cobalt-nickel-iron electroplating composition bath used to produce a thin film head having a saturation magnetization (4.pi.M.sub.s) of about 14K gauss, a coercivity (H.sub.c) of about 2 Oersteds, an anisotropy field (H.sub.k) of about 13 Oersteds and a permeability (.mu.) of about 1000.
It would be desireable to produce a thin film magnetic head having a yet smaller anisotropic field (H.sub.k) coercivity (H.sub.c), while maintaining a large saturated magnetization (M.sub.s or 4.pi.M.sub.s), and increasing the permeability (.mu.).